Scientists in China have cloned five monkeys after editing genes to induce several human diseases like Alzheimer's that they claim will help in medical research, an advance which is likely to raise fresh ethical concerns about gene-editing.

The announcement follows the recent confirmation that the world's first gene-edited human babies have been born in China, following an "unauthorised experiment" that has caused widespread disquiet in the scientific community.

Chinese scientists have cloned five monkeys from a gene-edited macaque with circadian rhythm disorders that are linked to sleep problems, depression and Alzheimer's disease, the official Xinhua news agency said on Thursday.

It is the first time multiple clones had been made from a gene-edited monkey for biomedical research, the news agency said.

Chinese Scientists made the announcement of the monkey cloning on Thursday with two articles published in National Science Review, a top Chinese journal in English.

The cloned monkeys were born in Shanghai at Institute of Neuroscience of Chinese Academy of Sciences.

Researchers said that the advance means that a population of customised gene-edited monkey models with uniform genetic background will be available for biomedical research.

Disorders of circadian rhythm are associated with many human diseases, including sleep disorders, depression, diabetic mellitus, cancer and neurodegenerative diseases, such as Alzheimer's disease.

Previously, mice and flies were widely used for the research of such diseases, but these animal models differ greatly from human beings in terms of activity routines, brain structure and metabolic rate.